System and Method for Improved Viewing and Navigation of Digital Images

ABSTRACT

A system and method for improved viewing and navigation of large digital images, such as whole slide images used in microscopy. The system and method displays the digital image along with movable navigation and field of view boxes that enable a viewer to pan the digital image in an accurate manner, and also performs automatic absolute reorientation of the digital image and automatic relative reorientation of subsequent digital images in relation to the first digital image.

CROSS REFERENCE TO RELATED APPLICATIONS

This patent application claims the benefit of U.S. Provisional PatentApplication No. 60/747,851, filed May 22, 2006, the entire content ofwhich is being incorporated herein by reference.

STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSOREDRESEARCH AND DEVELOPMENT

Portions of the present invention were made with support of the UnitedStates Government via a contract with the United States Air Force underContract No. DAMD 17-03-2-0017. The United States Government maytherefore have certain rights in the invention.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a system and method for improvedviewing and navigation of large digital images, such as whole slideimages used in microscopy. More particularly, the present inventionrelates to a system and method that displays the digital image alongwith movable navigation and field of view boxes that enable a viewer topan the digital image in an accurate manner, and also performs automaticabsolute reorientation of the digital image and the automatic relativereorientation of subsequent digital images in relation to the firstdigital image.

2. Description of the Related Art

Static images produced by microscope mounted cameras and robotictelepathology systems have been used for many years for clinicaltelepathology, largely for frozen section and other consultation. It iswidely accepted that the images produced by these systems providesufficient information for their intended purposes. While these systemsare useful for low volume applications such as frozen sections andconsultations, they are generally not practical for high volume usageapplications such as primary diagnosis, quality assurance, or diagnosticimmunohistochemistry. In addition, whole slide image systems produce asuperior image when compared to images produced by static image systems.Whole slide images are captured with greater resolution, wider dynamicrange, and often higher color fidelity.

As understood in the art, when using a microscope to view a slide image,the user (e.g., a pathologist) scans the slide of tissue at lowmagnification (e.g., 5× magnification) by slowly passing each portion oftissue underneath the lens. At this magnification, a small piece oftissue can result in, for example, 10 to 100 ‘fields of view’ that needto be screened for abnormalities. When an area of interest isidentified, the pathologist quickly switches to medium magnification(e.g., 10× magnification) to more closely examine the focus. Again, thepathologist slowly scans this now magnified area in the same manner, andif further resolution is required, the pathologist switches to a highermagnification objective (e.g., 20× magnification) for visualization ofeven further detail. The most important behavior to note is that the useof ‘smooth, slow panning’ to screen the slide is central to workflow, asa typical pathologist screens hundreds of glass slides per day.

The visual information contained in whole slide images is typicallysufficient for pathologists to make reliable diagnoses from whole slideimages alone. Recent targeted validation studies have concluded thatwhole slide images can be used in place of glass slides. As isunderstood in the art, large images, such as whole slide images inpathology, are difficult to navigate and scan when the image issignificantly larger than the field of view that can be represented on asingle screen. Large images are especially difficult to navigate overremote distances, that is, when the data is stored at one location andaccessed at another location. Since it is generally impractical to waitfor the transfer of the entire image file before the user can view theimage, selected regions of interest are delivered on demand as a streamof data into the field of view.

Current viewing instruments attempt to provide smooth, slow panning byusing either of two methods. The first is the click and drag method inwhich a mouse cursor typically is in the shape of a hand and navigationoccurs by clicking and dragging in a ratcheting manner. This results inhundreds of large hand movements per slide and is impractical for largevolume work. The second method employs a thumbnail navigator whereby themouse cursor is a box-shaped reticle on a low resolution thumbnail imageof the entire slide which represents the current field of view. The lowresolution thumbnail image is static, and the ‘field of view’ isdynamic. Moving the reticle moves the corresponding field of view. Thismethod can be generally well-suited for low objectives. However, as themagnification increases, the reticle size is reduced, and thesensitivity of movements is increased. That is, the same hand movementthat provided a smooth slow pan at low power results in a jerky,difficult to control movement at high power. Hence, users typicallycompromise by using the thumbnail navigator method at low power and theclick and drag method at high power. However, this compromise is veryinsufficient for high volume work.

In addition, anatomic pathologists typically examine several hundredglass slides per day during clinical practice. Specimens can besubdivided into classes based on their organ system, and subspecialtiesin pathology typically focus on a particular organ system. Pathologiststypically apply their diagnostic algorithms in a routine workflowbehavior (e.g. top-down, left-right) and the glass slides are deliveredto the pathologist in a consistent orientation. However, it isimpractical to perfectly orient the tissue on each instance of a glassslide, thus the pathologist manually orients the glass slide underneaththe microscope lens.

Anatomic pathologists also typically examine several ‘slices’ of atissue biopsy. When a biopsy is processed, it is typically fixed andembedded into a paraffin block, which is mounted on a microtome where ahistotechnologist shaves thin slices of the paraffin and tissue andplaces representative slices onto a glass slide. These glass slides arethen stained and delivered to a pathologist, who examines them under amicroscope for pathology. During the process of fixation and embedding,a fragment of a tissue biopsy assumes a unique shape. For example, acylindrical core biopsy from prostate tissue can curl into an ‘S’ shape.3-dimensional structures (such as glands or tumors) may be partiallypresent in the first slice, and become more apparent in subsequentslices. When a suspicious lesion is identified in one slice of tissue,corresponding foci of tissue in the adjacent slices must be identifiedand examined for similar pathology. In many types of biopsies, anabsolute orientation cannot be deduced. To identify corresponding fociof tissue amongst multiple slices on separate glass slides, thepathologist manually matches the foci of tissue. That is, if a lesionlies at the tip of the ‘S’ shape, the pathologist identifies the same‘S’ tip on the adjacent slices of tissue, keeping in mind that thetissue slice is likely not in the exact same orientation as the firstslice (unlike a CT scan in radiology). Furthermore, special stains areoften performed to help further identify suspicious lesions on glassslides. These special stains are performed on adjacent slices of tissue,and in these cases matching specific foci of tissue is also critical.

Currently, there does not exist a method to navigate and orient adigital slide as efficiently as one can with a glass slide.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects, advantages and novel features of the inventionwill be more readily appreciated from the following detailed descriptionwhen read in conjunction with the accompanying drawings, in which:

FIG. 1 is a conceptual block diagram of a workstation employing anembodiment of the present invention;

FIGS. 2-10 illustrate example of images displayed on the display screenof the workstation as shown in FIG. 1, and the manipulation of thoseimages, according to an embodiment of the present invention;

FIG. 11 a and 11 b illustrate an example of an absolute reorientation ofan image on the display screen of the workstation shown in FIG. 1according to an embodiment of the present invention; and

FIG. 12 illustrates an example of a relative reorientation of an imageon the display screen of the workstation shown in FIG. 1 according to anembodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

FIG. 1 is a block diagram illustrating an example of a workstation 100that can employ an embodiment of the present invention. As shown, atypical workstation 100 includes a display screen 102, a keyboard 104and a mouse 106. Naturally, the workstation 100 can be configured in anysuitable manner as would be appreciated by one skilled in the art.

As can be appreciated by, for example, scientists, physicians or otherpersonnel working in a laboratory setting, large images (such as wholeslide images used in pathology) are difficult to navigate and scan whenthe image is significantly larger than the field of view that can berepresented on the display screen 102. Accordingly, as discussed in moredetail below, an embodiment of the present invention enables theintuitive navigation of large images by the use of a smaller, onscreenthumbnail image representing the location of the current field of viewin the main display screen 102. These features can be embodied insoftware running on the workstation 100 or running at a remote site thatis accessible by the workstation 100 via, for example, the Internet, alocal area network (LAN), wide area network (WAN) or in any othersuitable manner.

As shown in FIGS. 1-10, the software according to an embodiment of thepresent invention generates an image 108 on the display screen 102,along with buttons or tabs 110 displayed at the top of the displayscreen 102. The buttons or tabs 110 can be accessed, for example, by themouse 106 to change the magnification of the image, cut and paste theimage, print the image, and so on. The software also generates a reticle112 and a thumbnail image 114 as shown. The image 108 that is displayedon the majority of the display screen 106 is that which is contained inthe reticle 112 in the thumbnail image 114. In other words, the reticle112 represents the current field of view that is shown as image 108, andcan be dynamically updated in several different ways.

For example, a user has the ability to increase and decrease levels ofnative or optical magnification. Accordingly, the software generates themagnification level of the thumbnail image 114 to trail the currentfield of view image 108 by a magnification ratio or factor, allowing fora consistent ratio of hand movements of the mouse 106, for example, toscreen navigation across different magnification levels. The softwarefurther tunes this ratio by increasing or decreasing the sensitivity ofthe mouse 106 across magnification levels.

If the thumbnail image 114 does not represent the entire image, movementof the reticle 112 to the periphery of the thumbnail image 114 willenable both the thumbnail image 114 and the field of view image 108 tobe dynamically updated with the adjacent areas of the thumbnail image114 that come into view as discussed below. That is, the software willin a sense scroll the thumbnail image 114 in the direction in which thereticle 112 is being moved once the reticle 112 reaches an edge of thecurrent thumbnail image 114 being displayed. Specifically, in oneexample, the software according to an embodiment of the presentinvention creates multiple streams of data that are synchronized witheach other. For instance, one stream of data can represent the thumbnailimage 114, and the second can represent the reticle 112 and whole screenimage 108, or alternatively, separate synchronized streams of data canrepresent the whole screen image 108, reticle 112 and thumbnail image114. In either configuration, the software according to an embodiment ofthe present invention updates the streams of data continuously anddynamically in an efficient manner such that the user does not perceivea dramatic slowdown in performance. The embodiment of the presentinvention therefore addresses the problem of losing useful context andorientation when screening and navigating large digital images at a highmagnification, and enables a smooth, slow pan across all magnificationsof a large image, regardless of the level of magnification.

The following description, along with FIGS. 1-10, provides an example ofthe manner in which the embodiment of the present invention describedabove can be used to view a whole slide image.

As discussed above, FIG. 1 illustrates an example of a workstation 100employing an embodiment of the present invention. FIGS. 2 and 3illustrate an example of two different whole screen images 108 beingdisplayed at a 10× magnification. As indicated in both figures, theimage displayed in the reticle 112 is at 10× magnification andcorresponds to the whole screen image 108, while the thumbnail image 114is at 5× magnification. As discussed briefly above, the dual images(reticle 112 and thumbnail image 114) allows for smooth, slow panning atany objective magnification. As shown, for example, in FIG. 4, when themagnification of the reticle 112 is increased to 20×, the magnificationof the whole screen image 108 increases to 20×, and the magnification ofthe thumbnail image 114 increases to 10×. Hence, the thumbnail image 114continues to lag the field of view of the whole screen image 108 andreticle 112 by one objective. This maintains a constant reticle size,maintaining a 1:1 ratio of mouse movements to screen panning throughoutthe spectrum of objectives. Smooth, slow panning is therefore uniformacross all magnifications. It is also noted that during changes inmagnification, the centers of the fields of view of the whole screenimage 108, the reticle 112, and the thumbnail image 114 are maintained.

More particularly, the thumbnail image 114 itself is able to dynamicallyand automatically “slow pan” when the reticle 112 reaches the peripheryof the thumbnail image 114 as shown in FIGS. 5 and 6. A user can use themouse 106, for example, or the arrow keys on the keyboard 104, or anyother suitable device or technique such as a wand (not shown) or voicerecognition control, to control the software to move the reticle image112. As shown in FIG. 5, the reticle 112 is moved to reach the top edgeof the thumbnail image 114. In this example, the arrow 118 indicates theposition of the cursor that is controlled by the mouse 106, so thereticle 112 can be dragged, for instance, by the mouse 106. In thisexample, when the user continues to pan the reticle 112 upward towardthe edge of the thumbnail image 114, the software according to anembodiment of the present invention will generate images so that thethumbnail image 114 appears to pan in the direction in which the reticle112 is being moved as shown in FIG. 6. As can be appreciated from FIG.6, the reticle 112 and the corresponding whole screen image 108 isfurther up the thumbnail image 114. This processing can be accomplished,for example, by using two steams of data, namely, one stream thatrepresents the thumbnail image 114 and the other that represents thereticle 112 and corresponding whole screen image 108. The softwareprocesses the two streams of data in the appropriate manner to generatea display on the display screen 102 that provides this slow pan effectof the image. It is further noted that if, for example, the data isbeing accessed by the workstation 100 from a remote site (e.g., a server120 as shown in FIG. 1), bandwidth can be conserved by accessing onlythe data necessary to generate the thumbnail image 114, reticle 112 andwhole screen image 108 at a particular time. Additional data can beaccessed as the reticle 112 is moved against the edge of the thumbnailimage 114 to create the panning effect.

FIGS. 7-10 further illustrate the slow pan of an image in which thereticle 112 is moved to the left edge of the thumbnail image 114 to thuspan the image to the left. It should be noted that the embodiment of thepresent invention enables the reticle 112 to move in any manner, such asvertically, horizontally, diagonally or in any combination, so that thereticle 112 can track any mouse movement by the user. The software cancontrol the display to maintain the reticle 112 in the last positionwhen the user stops moving the reticle 112, and can alternativelycontrol the display of the reticle 112 so that the reticle 112 returnsto the center of the thumbnail image 114 when released by the user(e.g., when the user stops moving the reticle 112).

It should also be noted that the embodiment of the present inventiondiscussed above can be configured to display on the display screen 102multiple thumbnail images 114, each containing a respective reticle 112.The user, for example, can position the arrow 118 on a desired thumbnailimage 114 to select that thumbnail image 114, in which event thesoftware controls the display to display as the whole screen image 108the image within the reticle 112 of that selected thumbnail image 114 inthe manner as discussed above. The user can then move the reticle 112 tomanipulate the display of the whole screen image 108 as discussed above.When the user wishes to select another thumbnail image 114, the userpositions the arrow 118 on that different thumbnail image 114, in whichevent the software controls the display 102 to thus display as the wholescreen image 108 the image within the reticle of that different selectedthumbnail image 114. The user can then move the reticle 112 tomanipulate the display of the whole screen image 108 as discussed above.In this way, the user can quickly flip through different thumbnailimages of the same whole slide image or different whole slide images forcomparison.

The embodiment of the present invention described above, in particular,the software employed in or accessed by the workstation 100, can befurther configured to perform absolute re-orientation of whole slideimages. In particular, an embodiment of the present invention willrotate a histopathological image according to a pre-determinedorientation based on the class of tissue of the image being displayed.Consistently oriented digital histopathological images will enhanceapplication of diagnostic algorithms by pathologists when evaluating aspecimen. The reorientation can be applied at time at which the image iscaptured or during presentation to the user. By being capable ofrecognizing the orientation of the tissue in the image, and providingcoordinates to properly re-orient the image of the tissue, orimmediately re-orient the image of the tissue without providingcoordinates, the embodiment of the present invention thus streamlinespathology workflow when examining histopathological images.

As can be appreciated by one skilled in the art, when a biopsy, forexample, is performed, the sample is sent to pathology for processing.The sample is typically fixed and embedded in a paraffin block. Ahistotechnologist places the block in a microtome, which shaves slicesof tissue off of the surface of the block. Selected slices are placedonto glass slides, then stained and delivered to the pathologist.Certain types of specimens are typically consistently oriented in thesame manner. For example, a skin biopsy will typically be oriented withthe epidermis on top and the subcutaneous tissue on bottom. Pathologistsare less prone to commit errors when a routine diagnostic algorithm canbe followed. When a specimen is incorrectly oriented, the routine isdisturbed. On an improperly oriented glass slide, the routine ispreserved by manually rotating the glass slide to the properorientation.

According to an embodiment of the present invention, the softwareemployed in or accessed by the workstation 100 recognizes specific typesof tissues in a whole slide image and re-orients those images prior todelivery to the pathologist. That is, the software is capable ofanalyzing a digital histopathological image of a specific tissue type(e.g. skin), detecting the proper orientation of the tissue fragment andgenerating a display that properly orients the image. In the case of across section of a skin specimen, the software is capable of detectingthe superior skin surface and the inferior subcutaneous tissue, and thenrotating the image to a predetermined orientation.

In one example, as shown in FIG. 11 a, a database that is accessible bythe software can be programmed to include data representing apredetermined orientation for each of a plurality of specific specimentypes (e.g., tissue classes), and data representing a correspondingtarget set of images 122-1 through 122-n. When the software analyzes theimage to be displayed, the software can compare the image 108 to thetarget set of images 122-1 through 122-n to determine the appropriateorientation for that type of image. The software can then generate thewhole screen image 108 having the desired orientation (e.g., in thiscase, that of target image 122-3) as shown, for example, in FIG. 11 b.In doing so, the software can produce coordinates with which tore-orient the image along with, for example, metadata pertaining to there-orientation that indicates an amount of needed rotation change indegrees. The preferred event or time to trigger the automaticre-orientation algorithm can be when the image is incorporated andstored in the system. The automatic re-orientation need not be apermanent change to the captured image, but rather, as discussed above,the software can calculate the needed coordinates and store theparameters and values associated with the image in a database, forexample. Alternatively, the original image can be stored and there-orientation can be performed when the display is being generated. Theembodiment of the present invention can also allow a pathologist to undoand redo the changes in image orientation as dictated by their workflow.

Accordingly, as can be appreciated from the above, the embodiment of thepresent invention is capable of detecting the orientation of a giventype of tissue image, providing coordinates at which the tissue image isto be rotated, and rotating the tissue image prior to display so thatthe tissue image is displayed at the proper orientation.

In addition, as shown in FIG. 12, the embodiments of the presentinvention described above can be further configured such that thesoftware employed in or accessible by the workstation 100 can analyzeand orient an image 108 of a fragment of histopathological tissue, andthen, taking that initial image 108 as a reference tissue image, willorient subsequent images of the tissue 108-1, 108-2, 108-3 and so on, inan orientation similar to the reference tissue image. The software willalso be able to, given a specific focus of tissue on the original image,identify the same areas of tissue on subsequent images of tissue. Theembodiment of the present invention will therefore further streamlinepathology workflow for examining histopathological images.

As discussed in the Background section above, when a biopsy is processedit can assume a unique shape. For example, a long string-like prostatebiopsy can assume an S-shape. Several slices of that S-shaped biopsywill be placed on glass slides, and a small focus is usually present inmore than one of those slides. Taken individually, those foci may notrepresent an abnormality (e.g., a small focus of cancer glands), buttaken as a whole can confirm the diagnosis. It is much more difficultfor histotechnologists to orient these types of specimens and therefore,the pathologist typically has to manually match foci of tissue ondifferent slides by manual rotation.

As discussed above, according to an embodiment of the present invention,the software orients a reference whole slide image 108 (e.g., the first‘slice’) to the appropriate orientation using the absolutere-orientation techniques discussed above. The software will thenspecify a set of subsequent images 108-1, 108-2, 108-3 and so on of thesample on which to perform the re-orientation processing prior todisplaying those images. As with the absolute re-orientation asdiscussed above, the software will produce coordinates with which tore-orient the images along with metadata pertaining to there-orientation process, including the amount of needed rotation changein degrees for each image. The automatic re-orientation of the imagescan be performed when each image is read into the system, or can occurjust prior to displaying the image on the display screen 102. The user(e.g., a pathologist) can use the keyboard 104 or any other suitabletool to manipulate the images as discussed above, and to undo and redothe changes in orientation as desired. As with the absolutere-orientation, the automatic relative re-orientation is not a permanentchange to the data representing each of the whole slide images, butrather includes data associated with the images that represents thecoordinates, parameters and values associated with the properre-orientation of the image. In addition, when a user (e.g.,pathologist) uses the reticle 112 and thumbnail image 114, for example,to identify a focus of interest on an image (e.g., on an image of aslice of tissue), the software will either automatically position thereticle 112 to locate that same area of interest on subsequent adjacentimages (e.g., adjacent tissue slices) or flag the area on a lower power.

Accordingly, as can be appreciated from the above, the embodiment of thepresent invention can potentially be incorporated into any softwareproduct able to view large images, including software suites designed toassist pathologists in remotely examining whole slide images. A productsuch as this has the potential to become a Picture Archiving andCommunication System (PACS) for whole slide images in pathology. Asunderstood by one skilled in the art, PACS systems are integralcomponents of modern health systems today and provide much of the visualinformation contained within the electronic medical record.

Although only a few exemplary embodiments of the present invention havebeen described in detail above, those skilled in the art will readilyappreciate that many modifications are possible in the exemplaryembodiments without materially departing from the novel teachings andadvantages of this invention. Accordingly, all such modifications areintended to be included within the scope of this invention.

1. A method for displaying an image of a biological sample, the methodcomprising: generating a display of the image on a display screen, thedisplay comprising a thumbnail image representing an area of thebiological sample, a reticle image within the thumbnail image, and awhole screen image corresponding to the reticle image and occupying moreof the display screen than the thumbnail image; and generating amodified display of the image based on movement of the reticle image tosimulate scanning of the image, such that when the reticle image becomesproximate to an edge of the thumbnail image, the thumbnail image andreticle image within the thumbnail image are modified to simulatemovement of the thumbnail image and reticle image to another area of thebiological sample, and the whole screen image is modified to correspondto the modified reticle image.
 2. A method as claimed in claim 1,wherein: the display generating step generates the thumbnail imagerepresenting an area of the biological sample at a first magnificationpower and generates the whole screen image at a second magnificationpower greater than the first magnification power.
 3. A method as claimedin claim 2, further comprising: changing the display of the image on thedisplay screen to increase the first magnification power and, inresponse, increasing the second magnification power by a proportionateamount.
 4. A method as claimed in claim 3, wherein: the proportionateamount is a one to one ratio between the increase in the firstmagnification power and the increase in the second magnification power.5. A method as claimed in claim 1, wherein: the generating steps areperformed at a workstation; and the method further comprises operatingthe workstation to obtain, from a location remote from the workstation,data representing the thumbnail image, the reticle image and the wholescreen image based on which the step of generating the display of theimage generates the thumbnail image, the reticle image and the wholescreen image.
 6. A method as claimed in claim 1, wherein: the generatingsteps are performed at a workstation; and the method further comprisesoperating the workstation to obtain data in respective data streams,with one data stream including data representing the thumbnail image, asecond data stream including data representing the reticle image and athird data stream including data representing the whole screen image,based on which the step of generating the display of the image generatesthe thumbnail image, the reticle image and the whole screen image.
 7. Amethod for displaying an image of a biological sample, the methodcomprising: storing sample data representing images of different typesof biological samples; comparing image data representing a section of abiological sample to the sample data to identify a type of biologicalsample represented by the image data; and generating a display of thesection of the biological sample represented by the image data on adisplay screen at a certain orientation based on the type of biologicalsample represented by the image data as determined by the comparingstep.
 8. A method as claimed in claim 7, further comprising: generatinganother display of another section of the biological sample based on atleast one additional image data representing said another section of thebiological sample, such that an orientation at which said anotherdisplay is displayed on the display screen is consistent with thecertain orientation at which the display of the section of thebiological sample was displayed on the display screen.
 9. A method asclaimed in claim 8, further comprising: continuing to generateadditional displays of additional sections of the biological samplebased on further image data representing the additional sections, suchthat a respective orientation at which each said additional display isdisplayed on the display screen is consistent with the certainorientation at which the display of the section of the biological samplewas displayed on the display screen.
 10. A method as claimed in claim 7,wherein: the generating step is performed at a workstation; and themethod further comprises operating the workstation to obtain, from alocation remote from the workstation, the sample data and the imagedata.
 11. A computer readable medium of instructions for controlling acomputer to display an image of a biological sample, the instructioncomprising: a first set of instructions for controlling the computer togenerate a display of the image on a display screen, the displaycomprising a thumbnail image representing an area of the biologicalsample, a reticle image within the thumbnail image, and a whole screenimage corresponding to the reticle image and occupying more of thedisplay screen than the thumbnail image; and a second set ofinstructions for controlling the computer to generate a modified displayof the image based on movement of the reticle image to simulate scanningof the image, such that when the reticle image becomes proximate to anedge of the thumbnail image, the thumbnail image and reticle imagewithin the thumbnail image are modified to simulate movement of thethumbnail image and reticle image to another area of the biologicalsample, and the whole screen image is modified to correspond to themodified reticle image.
 12. A computer readable medium of instructionsas claimed in claim 11, wherein: the first set of instructions controlsthe computer to generate the thumbnail image representing an area of thebiological sample at a first magnification power and generates the wholescreen image at a second magnification power greater than the firstmagnification power.
 13. A computer readable medium of instructions asclaimed in claim 12, further comprising: a third set of instructions forcontrolling the computer to change the display of the image on thedisplay screen to increase the first magnification power and, inresponse, increasing the second magnification power by a proportionateamount.
 14. A computer readable medium of instructions as claimed inclaim 13, wherein: the proportionate amount is a one to one ratiobetween the increase in the first magnification power and the increasein the second magnification power.
 15. A computer readable medium ofinstructions as claimed in claim 11, further comprising: a fourth set ofinstructions for controlling the computer to obtain, from a locationremote from the computer, data representing the thumbnail image, thereticle image and the whole screen image based on which the thumbnailimage, the reticle image and the whole screen image and generated.
 16. Acomputer readable medium of instructions as claimed in claim 11,wherein: a fifth set of instructions for controlling the computer toobtain data in respective data streams, with one data stream includingdata representing the thumbnail image, a second data stream includingdata representing the reticle image and a third data stream includingdata representing the whole screen image, based on which the thumbnailimage, the reticle image and the whole screen image are generated.
 17. Acomputer readable medium of instructions for controlling a computer todisplay an image of a biological sample, the instructions comprising: afirst set of instructions for controlling the computer to store sampledata representing images of different types of biological samples; asecond set of instructions for controlling the computer to compare imagedata representing a section of a biological sample to the sample data toidentify a type of biological sample represented by the image data; anda third set of instructions for controlling the computer to generate adisplay of the section of the biological sample represented by the imagedata on a display screen at a certain orientation based on the type ofbiological sample represented by the image data as determined by thecomparison of the image data and the sample data.
 18. A computerreadable medium of instructions as claimed in claim 17, furthercomprising: a fourth set of instructions for controlling the computer togenerate another display of another section of the biological samplebased on at least one additional image data representing said anothersection of the biological sample, such that an orientation at which saidanother display is displayed on the display screen is consistent withthe certain orientation at which the display of the section of thebiological sample was displayed on the display screen.
 19. A computerreadable medium of instructions as claimed in claim 18, wherein: thefourth set of instructions further controls the computer to continue togenerate additional displays of additional sections of the biologicalsample based on further image data representing the additional sections,such that a respective orientation at which each said additional displayis displayed on the display screen is consistent with the certainorientation at which the display of the section of the biological samplewas displayed on the display screen.
 20. A computer readable medium ofinstructions as claimed in claim 17, further comprising: a fifth set ofinstructions for controlling the computer to obtain, from a locationremote from the computer, the sample data and the image data.